5/10/13 11:57 AM EDT

Today's blockbuster ABC News report about White House and State Dept. involvement in revising the CIA’s Benghazi talking points has provided Republicans with new talking points in their effort to discredit former Sec. of State Hillary Clinton. But Jonathan Karl, the ABC News White House correspondent who landed the scoop, says not so fast.

The emails obtained by Karl show that State Dept. spokesman Victoria Nuland raised objections to a paragraph in the talking points mentioning threats from extremists linked to Al Qaeda. When a round of revisions did not satisfy her concerns, she wrote back: “These changes don’t resolve all of my issues or those of my building's leadership."

In that reference to the "building's leadership," some see a reference to Sec. Clinton. But Karl says that to date, no such evidence exists.

"There's no evidence that I've seen that Hillary Clinton was aware of what was going on, or in any way tried to direct what was in these talking points," Karl told POLITICO on Friday morning. "But that sentence is certainly open to interpretation, and you can guarantee it is going to seized on by Republicans for a long time, because ultimately the leadership of that building is Hillary Clinton."

Republicans have been fighting to keep the Benghazi story alive for months, and the right-wing blogosphere has made it their r'aison d'etre. Despite front page reports in the New York Times and scoops from reporters like Karl, conservatives accuse the mainstream media of failing to adequately investigate the story.

Those accusations are likely to subside this weekend in the wake of Karl's report (and that of The Weekly Standard's Stephen Hayes), which comes on the heels of Wednesday's 'emotional' testimony from three State Dept. officials. Benghazi is now driving the news cycle and -- as my colleagues Glenn Thrush and Maggie Haberman pointed out on Thursday -- Hillary Clinton is once again fair-game for critics.

The Sunday shows will be almost entirely dedicated to the issue: ABC's "This Week," will feature interviews with Sens. John McCain and Jack Reed, and Gen. James Cartwright, retired Vice Chairman of the Joint Chiefs of Staff, will join the roundtable. CBS's "Face The Nation" will feature interviews with former Sec. of Defense Robert Gates and Sens. Dick Durbin and Kelly Ayotte. NBC's "Meet The Press" will have exclusive interviews with House Oversight Committee Chair Darrell Issa and Senate Intelligence Chair Dianne Feinstein.

But where the story goes after Sunday is anyone's guess.

"I have no idea how long this story will go on, but what is clear after this week is that there are still legitimate questions to be asked, and there's also going to be a political story regarding Hillary Clinton," Karl told POLITICO. "The story clearly has legs -- for how long, I just don't know."